Machine clamp



Bam l, W24 l,79,27

H. CADWALLADER, JR

MACHINE CLAMP Filed March l5. 1921 www:

Patented dan. l, 1924.

attain HARRY CDWALLADER, JR., OF PHILADELPHIA, PENNSYLVANIA.

MACHINE CLAMP.

Application led March 15, 1921. Serial No. 452,558.

To alZZ- to hom. t may concern Be it known that I, HARRY CADWALLADER,Jr., a citizen of the United States, and a resident ot Philadelphia.,county ot' Philadelphia., State ot' Pennsylvania, have invented certainnew and useful Improvements in Machine Clamps, o't which the followingis a specification.

The present application is a continuation in part ot application tiledMarch 13, 1919, Serial No. 282,453 now Patent 1,376,077,

' Apr. 26, 1921, as to all matter common to the two applications.

Some of the objects of the present invent-ion are to provide a clamp formachine shop practice to hold a piece of work in a rigid iXed positionupon a support; to provide clamping means arranged to direct the appliedtorce substantially at right angles to the face ot the work engaged bythe clamp; to provide clamping means which acts to self-adjust the clampto the work; to provide a clamp arranged to co-act with work materialwhich is not provided with lugs or flanges capable of being engaged bya. clamp; and to provide other improvements as will hereinafter appear.

1n the accompanying drawings Fig. 1

represents a side elevation of an end clamp l embodying one form of thepresent invention; Fig. 2 represents a bottom plan of the same; Fig. 3represents the clamp of Fig. 1 in an operative position; Fig. 4represents a side elevation ot another form of the invention; Fig. 5represents an eleva.- tion of one end ot the clamp shown in Fig. 3; Fig.6 represents an elevation of the other end of the clamp shown in Fig. 3;and Fig. '7 represents the clamp ot Fig. 4 in an operative position.

Referring to the drawings, the form of the invention shown in F igs. 1and 2 consists of a body 10 formed of material designed to withstandbending, shearing or other stresses or strains and generally of acharacter to stand up under the rough use of a machine shop. The body 10in this construction is of bifurcated form providing two substantiallyparallel legs 11 which provide an open ended slot 12 between themthrough which a suitable bolt 13 or other clamp-ing means can be passedto rigidly secure the body 10 to the supporting table to clamp the workrigidly in place. The elongated slot 12 permits a desirable range otladjustment for the clamping bolt 13.

To provide self-adjusting means whereby the clamping body 10automatically seats upon the work in a manner to direct the appliedforce substantially at right angles to the work, the legs l1 arerespectively provided with rounded projections 14 which act as grippingjaws engaging the work or a support. These projections 14 serveeffectively upon an inclined or an irregular surface equally as well asupon a plane surface because the curved face permits the point ofapplication to automatically shift under the different conditions.Preferably the opposite face of each of the legs 11 is bevelleol asindicated at 15 so that the gripping ends have a dimension readilyadapting` them to restricted locations.

*or supporting the other end of the body l0, a lug or stein 16 is formedintegral with the body 10 and is arranged to be inserted in a hole 17 inthe work or a support, drilled for the purpose, or in any convenientrecess or other location. l/Vhen the work has projecting ledges orflanges the lug 16 can be seated directly thereon as will be understood.

In Figs. 4, 5 and 6 another form of the invention is shown wherein theend of the clamp body 10 which carries the lug 16 is provided with atransverse boss or rib 2O eX- tending substantially the width of thebody 10. This rib 20 is symmetrically curved from end to end, as shownin Fig. 5, to provide a contour by which the body 10 is selfadjustingabout its longitudinal axis when seated upon the work to be clamped orupon a support. Furthermore, this curved contact surface is roundedlaterally, as shown in Fig. 4, to provide means for causing the body 10to assume such a position as to direct the applied face substantially atright angles to the work or the support. This rib 20 therefore serves toprovide a maximum contact surface for clamping purposes, insuresvertical pressure at all times, and gives a bearing surface which iseective substantially regardless of the angularity of the work. In thisorm of the invention the body 10 likewise is of bifurcated form havingthe legs 2l and rounded end projections 22 upon each as previouslydescribed.

As `a means for reinforcing the body t0 prevent fractures adjacent thepoints of contact or other portions of the legs when under stress, eachleg is formed with a depending flange 23 which increases in depth ofboth ends ot the clamp body, thus building up the mid-section of thelegs 2l to resist stresses and distribute vthem through the metalinstead of acting as a direct shear.

From the foregoing it will be evident that at one end of the body l0,the projections 22 are tangent to a plane parallel to the bottom of thebody, while at the other end oit the body the transverse curved rib 2Oallows the body l to oscilla-te so that the parallel projections 22 canseat properly upon the work.

The clamp oit the present invention is arranged under all workingconditions to rigidly hold the work without slipping and when used withwork at an angle is very f e'lieetive because the rounded jaws can gripthe work rigidly, whichV is not the case where a clainp with. a sharpcorner is employed.

Although but two of the many forms in which this invention may beembodied are shown, it is to be understood that the invention is notlimited to any specific construction but might be applied in variousforms .vithout departing ironi the spirit of the invention or the scopeof the appended claims.

Having thus described my invention, I claim:

l. ln a clamp for machine work, the combination ot a body otsubstantially U-shape forming a pair oi: jaws, each jaw having a4rounded gripping surface, a lug axially disposed at the opposite endo'l' said body from said jaws and arranged to be inserted in an openingformed in the material to be clamped, and means to clamp said body inoperative position.

2. In a clamp for machine work, the coinbination of a body ofsubstantially U-shape forming a pair of jaws, a' lug axially disposed atthe opposite end oi? said body 'from said jaws and arranged to beinserted in an opening iforined in the inaterial to be clamped, means toclamp said body in 'operative position, and self-adjusting ineens t'oreach jaw.

ln a` clamp, a body, a rounded projection formed at one end portion oi"said body for engaging the work or a support, a transversely rounded ribat the other end portion ot said body, also for engaging the work or asupport, said rib having its Contact face curved, and means to clampsaid body with said projection and rib engaging the work or a support.

4. In a clamp, a body, rounded projections formed at one end portion ofsaid body the outer contact faces thereoiz lying in a plane parallel tothe bottoni ot said body, a transverse rounded rib at the other endportion ol" said body, said rib having its Contact face curved from endto end of said rib, and means to clamp said bod-y with said projectionsand rib engaging the work or a support.

5. In a clamp, a body, rounded projections iiormed at one end portion ofsaid body, said projections being arranged to simultaneously contactwith a surface, a transverse rounded rib at the other end portion otsaid body, depending flanges respectively at opposite sides oli saidclamp,

and means to clamp said body with said projections and rib engaging thework or a support.

6. ln a clamp, a body, rounded projections formed at one end portion ofsaid body, said projections being arranged to simultaneously contactwith a surface', a transverse rounded rib at the other end portion ofsaid body, depending flanges respectively at opposite sides of saidclamp, said iianges being greatest in depth at inidseetion, and means toclamp said body with said projections and rib engaging the work or asupport.

Signed at Philadelphia, in the county of Philadelphia, and State ofPennsylvania, this 8th day of March, 1921.

HARRY GADVVALLABER, JR.

